With my car, both does not work. You've to give the steering wheel a little push first for lane change. And while it detects the speed, it does not adjust to it (autopilot V1).
That's so weird. So, mine has done lane change with ONLY the indicator lever for a long time. Recently, aka last month or two, an update has clearly been pushed that has significantly increased the smoothness of the lane changes. It used to be very aggressive. My friend has confirmed the behavior change as well. I have a AP1 car as well, 2016 Refresh P90DL but my wife's and my friends are the pre-refresh cars with AP1. One thing is the indicator has to be held until the lane change is about 80% complete aka you can't just flick the lever and expect it to lane change. Try holding the lever in the direction you want to go until the car has passed over the dotted line and then let go.
Also, there is a setting that states how far above the speed limit you wish to allow the car to go. You might want to check that. My car slows down (I have it set to 10mph above the speed limit) when it sees a lower speed limit aka on my drive home, it goes from 45 mph limit to 35 mph and the car slows down.